Absolute numbers
Relative GNO were calculated monthly for 2018:
See Genolini et al. (2015) at https://www.jstatsoft.org/article/view/v065i04
No clear evidence for optimal amount of clusters
##
## x <categorical>
## # total N=335 valid N=335 mean=1.45 sd=0.54
##
## val frq raw.prc valid.prc cum.prc
## A 191 57.01 57.01 57.01
## B 136 40.60 40.60 97.61
## C 8 2.39 2.39 100.00
## <NA> 0 0.00 NA NA